Task #[NUMBER] for StackableItems v1.2.0 generated an exception: java.lang.AssertionError: TRAP

[Greymagic27]

This is an error that appears at random points in my server and I haven't found the exact cause yet. The full error is as follows:

[02:32:35] [Server thread/WARN]: [StackableItems] Task #4491128 for StackableItems v1.2.0 generated an exception
java.lang.AssertionError: TRAP
    at net.minecraft.world.item.ItemStack.updateEmptyCacheFlag(ItemStack.java:251) ~[paper-1.19.3.jar:git-Paper-448]
    at net.minecraft.world.item.ItemStack.setCount(ItemStack.java:1290) ~[paper-1.19.3.jar:git-Paper-448]
    at org.bukkit.craftbukkit.v1_19_R2.inventory.CraftItemStack.setAmount(CraftItemStack.java:148) ~[paper-1.19.3.jar:git-Paper-448]
    at haveric.stackableItems.util.InventoryUtil.lambda$addItems$0(InventoryUtil.java:447) ~[StackableItems_20-06-2022.jar:?]
    at org.bukkit.craftbukkit.v1_19_R2.scheduler.CraftTask.run(CraftTask.java:101) ~[paper-1.19.3.jar:git-Paper-448]
    at org.bukkit.craftbukkit.v1_19_R2.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:483) ~[paper-1.19.3.jar:git-Paper-448]
    at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1473) ~[paper-1.19.3.jar:git-Paper-448]
    at net.minecraft.server.dedicated.DedicatedServer.tickChildren(DedicatedServer.java:447) ~[paper-1.19.3.jar:git-Paper-448]
    at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1397) ~[paper-1.19.3.jar:git-Paper-448]
    at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1173) ~[paper-1.19.3.jar:git-Paper-448]
    at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:316) ~[paper-1.19.3.jar:git-Paper-448]
    at java.lang.Thread.run(Thread.java:833) ~[?:?]```
This was tested on 1.19.3

[haveric]

Are you able to narrow down what specifically you were doing before this error occurred?

[Greymagic27]

It's only been noticed in the console after the fact and only when other users were online, not when I was online unfortunately.

I've got a suspicion the error is caused when crafting and shift clicking to craft in a custom stack. I'll try this later and send over any results

[Greymagic27]

If it is when you craft into a custom set stack then I can't reproduce it.

[CommandoEchino]

I have also experienced this issue. It started happening almost immediately after adding this plugin to my server. The culprit turned out to be one of my players stacking 64 totems in their inventory:

EDIT: They then did the same thing with a saddle, which had the same effect. What gives?

[CloudeLecaw]

we also have this issue on our server and dont use any Traps to stack.. we also dont know at the moment what causes this...

It's only been noticed in the console after the fact and only when other users were online, not when I was online unfortunately

same. i tried many things and dont know what our players are doing here that i cant do...

[06:56:32] [Server thread/WARN]: [StackableItems] Task #3682138 for StackableItems v1.2.0 generated an exception
java.lang.AssertionError: TRAP
    at net.minecraft.world.item.ItemStack.updateEmptyCacheFlag(ItemStack.java:254) ~[paper-1.19.4.jar:git-Paper-521]
    at net.minecraft.world.item.ItemStack.setCount(ItemStack.java:1321) ~[paper-1.19.4.jar:git-Paper-521]
    at org.bukkit.craftbukkit.v1_19_R3.inventory.CraftItemStack.setAmount(CraftItemStack.java:148) ~[paper-1.19.4.jar:git-Paper-521]
    at haveric.stackableItems.util.InventoryUtil.lambda$addItems$0(InventoryUtil.java:474) ~[StackableItems_1.2.0_SelfCompiled.jar:?]
    at org.bukkit.craftbukkit.v1_19_R3.scheduler.CraftTask.run(CraftTask.java:101) ~[paper-1.19.4.jar:git-Paper-521]
    at org.bukkit.craftbukkit.v1_19_R3.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:483) ~[paper-1.19.4.jar:git-Paper-521]
    at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1483) ~[paper-1.19.4.jar:git-Paper-521]
    at net.minecraft.server.dedicated.DedicatedServer.tickChildren(DedicatedServer.java:447) ~[paper-1.19.4.jar:git-Paper-521]
    at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1397) ~[paper-1.19.4.jar:git-Paper-521]
    at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1174) ~[paper-1.19.4.jar:git-Paper-521]
    at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:320) ~[paper-1.19.4.jar:git-Paper-521]
    at java.lang.Thread.run(Thread.java:833) ~[?:?]

i recombiled the jar with the gradle from github to get a new file. but the new generated file has the same issue.

[AyalX]

We are also receiving this exception in console repeatedly:

[18:27:24 WARN]: [StackableItems] Task #923757 for StackableItems v1.2.0 generated an exception
java.lang.AssertionError: TRAP
        at net.minecraft.world.item.ItemStack.updateEmptyCacheFlag(ItemStack.java:255) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at net.minecraft.world.item.ItemStack.setCount(ItemStack.java:1346) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at org.bukkit.craftbukkit.v1_19_R3.inventory.CraftItemStack.setAmount(CraftItemStack.java:148) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at haveric.stackableItems.util.InventoryUtil.lambda$addItems$0(InventoryUtil.java:447) ~[StackableItems.jar:?]
        at org.bukkit.craftbukkit.v1_19_R3.scheduler.CraftTask.run(CraftTask.java:101) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at org.bukkit.craftbukkit.v1_19_R3.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:483) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1510) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at net.minecraft.server.dedicated.DedicatedServer.tickChildren(DedicatedServer.java:488) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1424) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1195) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:325) ~[purpur-1.19.4.jar:git-Purpur-1985]
        at java.lang.Thread.run(Thread.java:833) ~[?:?]

[haveric]

I have yet to be able to replicate this issue. If anyone who is experiencing it could help by zipping up their server and sending it to me for testing, that would be extremely helpful. Please feel free to reach out on discord as well.